DARRINGTON, Wash. — The rains that have bedeviled crews searching for victims in the debris field from the deadly Washington state mudslide are expected to ease this week, but searchers faced other challenges at the site like household chemicals and sewage.

Crews searching through the muck and devastation wrought by Washington's deadly mudslide are finding more human remains, bringing the official death toll to 24.

Seventeen of those 24 victims have been positively identified, the Snohomish County medical examiner's office said Monday afternoon. Previously, the official death toll was 21, with 15 victims identified.

More than two dozen people remain missing, authorities have said.

Steve Harris, a division supervisor for the search effort, said search teams are learning more about the force of the March 22 slide, and that is helping them better locate victims in a debris field that is 70 feet deep in places.

"There's a tremendous amount of force and energy behind this," Harris said of the slide. He didn't provide further details.

Searchers have had to contend with treacherous conditions, including household chemicals, septic tanks, gasoline and propane containers. When rescuers and dogs leave the site, they are hosed off by hazardous materials crews.

The March 22 landslide, one of the deadliest in U.S. history, struck a rural community about 55 miles northeast of Seattle.

The March 22 landslide, one of the deadliest in U.S. history, struck a rural community about 55 miles northeast of Seattle.